What’s New in the Patient Safety World

May 2014

Frequency of Diagnostic Errors in Outpatients



A new review shows that over 5% of outpatients have errors in diagnosis, about half of which may be potentially harmful (Singh 2014). The authors estimate that such errors in diagnosis may affect 12 million outpatients annually in the US.


In our March 2013 What’s New in the Patient Safety World column “Diagnostic Error in Primary Care” and our January 2014 What’s New in the Patient Safety World column “Trigger Tools to Prevent Diagnostic Delays” we highlighted previous studies by Singh and colleagues (Singh 2013, Murphy 2014)  on diagnostic errors in primary care that used trigger tool methodology. The new study included the previous work and a total of 3 studies using the same definitions and methodologies.


AHRQ, which partially funded the study, did a press release (AHRQ 2014) that also calls attention to the AHRQ toolkit “Improving Your Office Testing Process. A Toolkit for Rapid-Cycle Patient Safety and Quality Improvement” (see our October 2013 What’s New in the Patient Safety World column “New AHRQ Toolkit: Improving Your Office Testing”) and a new set of guides and interactive tools from the ONC to help health care providers more safely use electronic health information technology products, including test results reporting and follow up.


Diagnostic error, and specifically diagnostic error on the outpatient side, is finally receiving the attention it merits. It is important both in its frequent occurrence and the harm that results from it.



Some of our prior columns on diagnostic error:








Singh H, Meyer AND, Thomas EJ. The frequency of diagnostic errors in outpatient care: estimations from three large observational studies involving US adult populations. BMJ Qual Saf 2014; published online April 17, 2014




Singh H, Giardina TD, Meyer AND, et al. Types and Origins of Diagnostic Errors in Primary Care Settings. JAMA Intern Med 2013; published online February 25, 2013




Murphy DR, Laxmisan A, Reis BA, et al. Electronic health record-based triggers to detect potential delays in cancer diagnosis. BMJ Qual Saf 2014; 23: 8-16 Published Online First: 19 July 201




AHRQ. Diagnostic Errors Study Findings. Press Release April 16, 2014




AHRQ. Improving Your Office Testing Process. A Toolkit for Rapid-Cycle Patient Safety and Quality Improvement. August 2013




ONC (Office of the National Coordinator for Health Information Technology). Safer Guides. HealthIT.gov







Print “PDF version










Tip of the Week Archive


What’s New in the Patient Safety World Archive